This was only their third victory in 10 matches. They will finish nowhere near the playoffs again, but it's about pride now and theirs shone through in a display which will take some of the heat off the franchise and head coach Umaga.
The Ioane brothers, Akira and Rieko, again played massive parts for the Blues. They were dangerous throughout, with the younger Rieko scoring their team's opening try, but they were especially prominent at the end when it threatened to go, well, a little bit Bluesy again.
With the Waratahs boosted by a converted Michael Hooper try in the final 10 minutes, they found a new level of enthusiasm and spent the majority of it within the Blues' 40m territory. It was an Akira Ioane hit which turned a tackle into a maul and defused an attack and then it was a Rieko Ioane bootlaces tackle on the always dangerous Israel Folau which killed another.
"It's disappointing," Hooper said afterwards. "We created a lot of opportunities and then blew it right at the end there."
Up to Hooper's late try it was all relatively comfortable for the Blues and it wasn't as if they were doing anything special.
They just kept their shape on defence, and their wits on attack – unlike the Waratahs who are somehow still in the playoff mix and who seemingly couldn't resist the temptation to concede a penalty or a turnover.
Umaga's men played with patience and, against all type, a clinical attitude. They didn't try to score a try every time they got the ball as they have in the past; what they did do was try to ensure they got points every time they visited the opposition 22m area, and in the second half it was through Stephen Perofeta's boot.
Umaga's team have lost some close ones this season and in some matches they have looked very ordinary indeed. But here they looked reasonably cohesive and disciplined compared with a Waratahs side who, remarkably, are the best in Australia according to the Super Rugby table.
Folau, back from a hamstring injury for the home side and in his first match since publishing his whacky views on homosexuals on his social media platform, tried to get involved, but he was reasonably easily contained by the Blues' youngsters, including Orbyn Leger and debutant Caleb Clarke, and contributed to the visitors' first try to Rieko Ioane when shifting a crazy pass when under extreme pressure on his own line.
Dalton Papali'i's yellow card for a high tackle in the first half wasn't ideal, with hooker Damien Fitzpatrick scoring from a rolling maul immediately after, but right wing Tumua Manu hit back straight away with a try in the corner after a Perofeta break and offload and Matt Duffie's long pass.
In the second half they relied on grit but it was no less impressive.
Blues 24 (Rieko Ioane, Tumua Manu tries; Stephen Perofeta con, 4 pens)
Waratahs 21 (Damien Fitzpatrick, Sekope Kepu, Michael Hooper tries; Bernard Foley 3 cons)
HT: 18-14
